Smooth projective fibrations over the projective line and their sections

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

Member Seminar Speaker: Iacopo Brivio Title: Smooth projective fibrations over the projective line and their sections Abstract: Suppose $f\colon X\to \mathbf{CP}^1$ is a smooth projective fibration, is it then true that $f$ has a section? This deceptively simple result was established by Seidel and McDuff using deep methods of symplectic geometry. Alex Pieloch recently generalized this to morphisms […]

Topological to Gravitational Leptogenesis, via Ultra Unification 

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

Quantum Field Theory and Physical Mathematics Seminar Speaker: Juven Wang (LIMS, Royal Institution) Title: Topological to Gravitational Leptogenesis, via Ultra Unification Abstract: We propose a new mechanism for leptogenesis, named Topological Leptogenesis, in which dark matter consists of topological order, so gapped anyon excitations decay to generate the Standard Model lepton asymmetry. Topological Leptogenesis is in […]

The mass angular momentum inequality

Virtual

General Relativity Seminar Speaker: Gilbert Weinstein, Ariel University Title: The mass angular momentum inequality Abstract: We show that either there is a counterexample to black hole uniqueness, in the form of a regular axisymmetric stationary vacuum spacetime with an asymptotically flat end and multiple degenerate horizons which is ‘ADM stable’, or the following statement holds. […]

Blob homology

Science Center 507 1 Oxford Street, Cambridge

Geometry and Quantum Theory Seminar Speaker: Sunghyuk Park, Harvard CMSA Title: Blob homology

Quantum algebras and R-matrices from the equivariant affine Grassmannians

Virtual

Mathematical Physics and Algebraic Geometry Seminar Speaker: Wenjun Niu, Perimeter Institute Title: Quantum algebras and R-matrices from the equivariant affine Grassmannians Abstract: In this talk, I will explain my joint work with R. Abedin, in which we construct, for each Lie algebra g, a Hopf algebra and a spectral R-matrix satisfying quantum Yang-Baxter equation. This […]

Is every knot isotopic to the unknot?

Virtual

Freedman CMSA Seminar *via Zoom* Speaker: Sergey Melikhov, Steklov Math Institute Title: Is every knot isotopic to the unknot? Abstract: The following problem was stated by D. Rolfsen in his 1974 paper; according to R. Daverman it was being discussed since the mid-60s. Is every knot in $S^3$ isotopic (=homotopic through embeddings) to a PL knot --- […]

Event Series Foundation Seminar

Joint BHI/CMSA Foundation Seminar: Quantum Effects Inside Black Holes

Black Hole Initiative, 20 Garden Street, Cambridge MA CMSA, 20 Garden Street, Cambridge, MA, United States

Joint BHI/CMSA Foundation Seminar Location: BHI seminar room Speaker: Noa Zilberman (Princeton University) Title: Quantum Effects Inside Black Holes Abstract: Astrophysical black holes are known to be rotating. Within classical General Relativity, the simplest spacetime solution (the Kerr solution) describing a rotating black hole reveals a traversable passage through an inner horizon – which in […]

On 5d conformal matter

Virtual

Quantum Field Theory and Physical Mathematics Seminar Speaker: Mario De Marco (UL Brussels) Title: On 5d conformal matter Abstract: SCFTs with 8 supercharges lie at the sweet spot of the classification program of susy scale-invariant theories: with this amount of susy, the classification is in principle achievable, despite being non-trivial. In this talk, I will present […]

On the past maximal development of near-FLRW data for the Einstein scalar-field Vlasov system

CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

General Relativity Seminar Speaker: Liam Urban (University of Vienna) Title: On the past maximal development of near-FLRW data for the Einstein scalar-field Vlasov system Abstract: In recent years, the formation of Big Bang singularities has been increasingly well understood in presence of scalar-field matter, which suppresses the geometric oscillations that one generically expects otherwise. From a cosmological perspective, […]